shrpx: Added error handling when error_reply() failed

examples/shrpx_https_upstream.cc

@@ -145,8 +145,11 @@ int htp_hdrs_completecb(http_parser *htp)
 
   if(downstream->get_expect_100_continue()) {
     static const char reply_100[] = "HTTP/1.1 100 Continue\r\n\r\n";
-    bufferevent_write(upstream->get_client_handler()->get_bev(),
+    if(bufferevent_write(upstream->get_client_handler()->get_bev(),
-                      reply_100, sizeof(reply_100)-1);
+                         reply_100, sizeof(reply_100)-1) != 0) {
+      LOG(FATAL) << "bufferevent_write() faild";
+      return -1;
+    }
   }
 
   int rv =  dconn->attach_downstream(downstream);
@@ -154,7 +157,7 @@ int htp_hdrs_completecb(http_parser *htp)
     downstream->set_request_state(Downstream::CONNECT_FAIL);
     downstream->set_downstream_connection(0);
     delete dconn;
-    return 1;
+    return -1;
   } else {
     downstream->push_request_headers();
     downstream->set_request_state(Downstream::HEADER_COMPLETE);
@@ -229,7 +232,9 @@ int HttpsUpstream::on_read()
   if(htperr == HPE_PAUSED) {
     if(downstream->get_request_state() == Downstream::CONNECT_FAIL) {
       get_client_handler()->set_should_close_after_write(true);
-      error_reply(503);
+      if(error_reply(503) != 0) {
+        return -1;
+      }
       // Downstream gets deleted after response body is read.
     } else {
       assert(downstream->get_request_state() == Downstream::MSG_COMPLETE);
@@ -250,7 +255,9 @@ int HttpsUpstream::on_read()
         LOG(WARNING) << "Request Header too long:" << current_header_length_
                      << " bytes";
         get_client_handler()->set_should_close_after_write(true);
-        error_reply(400);
+        if(error_reply(400) != 0) {
+          return -1;
+        }
       } else if(downstream->get_output_buffer_full()) {
         if(ENABLE_LOG) {
           LOG(INFO) << "Downstream output buffer is full";
@@ -265,7 +272,9 @@ int HttpsUpstream::on_read()
                 << http_errno_description(htperr);
     }
     get_client_handler()->set_should_close_after_write(true);
-    error_reply(400);
+    if(error_reply(400) != 0) {
+      return -1;
+    }
   }
   return 0;
 }
@@ -359,7 +368,10 @@ void https_downstream_readcb(bufferevent *bev, void *ptr)
     } else {
       // We did not sent any HTTP response, so sent error
       // response. Cannot reuse downstream connection in this case.
-      upstream->error_reply(502);
+      if(upstream->error_reply(502) != 0) {
+        delete upstream->get_client_handler();
+        return;
+      }
       if(downstream->get_request_state() == Downstream::MSG_COMPLETE) {
         upstream->pop_downstream();
         delete downstream;
@@ -423,7 +435,10 @@ void https_downstream_eventcb(bufferevent *bev, short events, void *ptr)
       if(ENABLE_LOG) {
         LOG(INFO) << "Treated as downstream error";
       }
-      upstream->error_reply(502);
+      if(upstream->error_reply(502) != 0) {
+        delete upstream->get_client_handler();
+        return;
+      }
     }
     if(downstream->get_request_state() == Downstream::MSG_COMPLETE) {
       upstream->pop_downstream();
@@ -441,7 +456,10 @@ void https_downstream_eventcb(bufferevent *bev, short events, void *ptr)
       } else {
         status = 502;
       }
-      upstream->error_reply(status);
+      if(upstream->error_reply(status) != 0) {
+        delete upstream->get_client_handler();
+        return;
+      }
     }
     if(downstream->get_request_state() == Downstream::MSG_COMPLETE) {
       upstream->pop_downstream();
@@ -452,7 +470,7 @@ void https_downstream_eventcb(bufferevent *bev, short events, void *ptr)
 }
 } // namespace
 
-void HttpsUpstream::error_reply(int status_code)
+int HttpsUpstream::error_reply(int status_code)
 {
   std::string html = http::create_error_html(status_code);
   std::stringstream ss;
@@ -466,12 +484,16 @@ void HttpsUpstream::error_reply(int status_code)
   ss << "\r\n";
   std::string header = ss.str();
   evbuffer *output = bufferevent_get_output(handler_->get_bev());
-  evbuffer_add(output, header.c_str(), header.size());
+  if(evbuffer_add(output, header.c_str(), header.size()) != 0 ||
-  evbuffer_add(output, html.c_str(), html.size());
+     evbuffer_add(output, html.c_str(), html.size()) != 0) {
+    LOG(FATAL) << "evbuffer_add() failed";
+    return -1;
+  }
   Downstream *downstream = get_top_downstream();
   if(downstream) {
     downstream->set_response_state(Downstream::MSG_COMPLETE);
   }
+  return 0;
 }
 
 bufferevent_data_cb HttpsUpstream::get_downstream_readcb()

examples/shrpx_https_upstream.h

@@ -58,7 +58,7 @@ public:
   void pop_downstream();
   Downstream* get_top_downstream();
   Downstream* get_last_downstream();
-  void error_reply(int status_code);
+  int error_reply(int status_code);
 
   void pause_read(IOCtrlReason reason);
   void resume_read(IOCtrlReason reason);

examples/shrpx_spdy_upstream.cc

@@ -374,7 +374,10 @@ void spdy_downstream_readcb(bufferevent *bev, void *ptr)
     if(downstream->get_response_state() == Downstream::HEADER_COMPLETE) {
       upstream->rst_stream(downstream, SPDYLAY_INTERNAL_ERROR);
     } else {
-      upstream->error_reply(downstream, 502);
+      if(upstream->error_reply(downstream, 502) != 0) {
+        delete upstream->get_client_handler();
+        return;
+      }
     }
     downstream->set_response_state(Downstream::MSG_COMPLETE);
     // Clearly, we have to close downstream connection on http parser
@@ -383,7 +386,10 @@ void spdy_downstream_readcb(bufferevent *bev, void *ptr)
     delete dconn;
     dconn = 0;
   }
-  upstream->send();
+  if(upstream->send() != 0) {
+    delete upstream->get_client_handler();
+    return;
+  }
   // At this point, downstream may be deleted.
 }
 } // namespace
@@ -450,10 +456,16 @@ void spdy_downstream_eventcb(bufferevent *bev, short events, void *ptr)
       } else {
         // If stream was not closed, then we set MSG_COMPLETE and let
         // on_stream_close_callback delete downstream.
-        upstream->error_reply(downstream, 502);
+        if(upstream->error_reply(downstream, 502) != 0) {
+          upstream->get_client_handler();
+          return;
+        }
         downstream->set_response_state(Downstream::MSG_COMPLETE);
       }
-      upstream->send();
+      if(upstream->send() != 0) {
+        delete upstream->get_client_handler();
+        return;
+      }
       // At this point, downstream may be deleted.
     }
   } else if(events & (BEV_EVENT_ERROR | BEV_EVENT_TIMEOUT)) {
@@ -490,11 +502,17 @@ void spdy_downstream_eventcb(bufferevent *bev, short events, void *ptr)
           } else {
             status = 502;
           }
-          upstream->error_reply(downstream, status);
+          if(upstream->error_reply(downstream, status) != 0) {
+            delete upstream->get_client_handler();
+            return;
+          }
         }
         downstream->set_response_state(Downstream::MSG_COMPLETE);
       }
-      upstream->send();
+      if(upstream->send() != 0) {
+        delete upstream->get_client_handler();
+        return;
+      }
       // At this point, downstream may be deleted.
     }
   }
@@ -568,7 +586,7 @@ int SpdyUpstream::error_reply(Downstream *downstream, int status_code)
   rv = evbuffer_add(body, html.c_str(), html.size());
   if(rv == -1) {
     LOG(FATAL) << "evbuffer_add() failed";
-    DIE();
+    return -1;
   }
   downstream->set_response_state(Downstream::MSG_COMPLETE);